First powder coating, results so/so, anybody use the cheapo HF unit ? Options

[jsteele22]

Last night I finally got around to using the "Chicago Electric" powdercoating setup I bought at HF a couple of months ago. It was on sale, like $60, and others have reported satisfactory results with it. I had some problems, though, and wondered if anyone has any ideas to help.

The problem was that the powder delivery was very erratic. Whenever I pulled the trigger or jiggled the gun the tiniest bit, a huge blast of powder would come out. Huge. I'd say, 1/16" or so of powder would splat out onto the work. After the huge splurt, the powder would come out in a reasonable manner, and go right where it was supposed to. Gradually, though, the fog would get thinner and thinner, and I'd have to shake the gun a tiny bit. This produced another huge splurt, then another interval of acceptable flow. To get by, I had a scrap metal shield that I kept in front of the work until the splurt was over, then moved out of the way during the intervals of acceptable operation. It works, but it's tedious and messy.


The instructions say to either use 10-15 psi regulated at the compressor, or to use the regulator screw on the gun itself. I'm using the shop at my work, and the compressor is off in a different room that I don't have a key for. So I bought a cheapo HF regulator that I screwed onto the gun, and before loading it with power, tried to test the operation. With the trigger pulled, I could - barely - regulate the pressure, but as soon as I released the trigger, the pressure would climb to line pressure. The POS Chinese regulator wasn't regulating. Then, based on the instructions, I removed the regulator and tried regulating the air with the screw built into the gun. No way of knowing the pressure, but from the sound I could hear the rate of flow and trim it to something reasonable. In any case, the air flow is smooth and steady.

Any tips or suggestions ? The obvious thing to try is buy a non-crap regualtor. But has anyone had luck using the metering screw in the gun itself ? My hunch right now is that maybe I had the air flow too slow. How rapidly should the powder coat the work ?

TIA, Jeff

p.s. I'm off skiing tomorrow; won't be back until Tues.

[scotty b]

John part of my job is powder coating, both commercially and most of the time auto/motorcycle parts, and while I agree with you for the most part, in this particular application I don't see an IR light being able to sustain an appropriate temp to be able to cure the pieces. In an oven maybe, but I have personally experienced too low a temp in the oven and poor hardening of the powder. My situation was the controller temp was 100 deg off of the actual temp of the oven. That said we were baking parts at 325 instead of 425. If I understand what you are saying we could have simply increased the bake time to compensate?? If so that would make things a LOT easier. (IMG:style_emoticons/default/ohmy.gif) I simply turned the control temp up to 525 to compensate and kept the normal bake time. Do you sell non automated equipment ? I may need to talk to you in the near future !! (IMG:style_emoticons/default/thumb3d.gif) Yes I have also noticed gloss white really does not like to be jelled then baked, it turns yellowish